lab2.c

使用PIC24 16位单片机 读写SD卡 支持FAT32

// Lab2.c


#include "fileio.h"
#include "lcd.h"

#define linelength	16

void LCDwait (void);
void Delay(BYTE milliseconds);
void convert (WORD adres, char * stringres);
BYTE convertback (char * buffer);
unsigned int toBCD (unsigned int old);

int main (void)
{
	const char name[] = "datalog.txt";		// The name of the file

	unsigned int counter = 0x0000;
	unsigned int counterBCD = 0x0000;

	char bffr[6];		// The buffer to read from and write to

	FILE *  myFile;		// The pointer to your file

	WORD	result;		// The result of the A/D converstion

	BYTE	display;
	BYTE	count;

	OSCCON = 0x0000;

	TRISA	&= 0xff00;
	TRISD	&= 0xff3f;
	
	AD1PCFG = 0xFFDF;
	AD1CON3 = 0x0C05;
	AD1CON2 = 0xE000;
	AD1CHS	= 0x0505;
	AD1CON1 = 0x00E7;

	// Setup the LCD
	mLCDInit();
	LCDProcessEvents();
	LCDwait();
	mLCDHome();
	LCDProcessEvents();
	LCDwait();


/********************************************************************************
*	Line 1																		*
*	Write the function to initialize the card									*
*   If the function returns 0, the program should get trapped in the infinite   *
*   loop
********************************************************************************/
	if (!FAT16Init())
/*******************************************************************************/
	{
		LATA = 0xC0;
		while(1);
	}
	else
	{

/********************************************************************************
*	Line 2                                                                    	*
*	Fill in the arguments for the fopen function to write a file	          	*
********************************************************************************/
		myFile  = fopen (name,WRITE	);
/*******************************************************************************/

		if (myFile == NULL )
		{
			// Code was unsuccessful- infinate loop
			LATA = 0xE0;
			while(1);
		}
		else
		{
			while (PORTDbits.RD13)
			{
				AD1CON1bits.ADON = 1;
				while ( ! AD1CON1bits.DONE)
				{
					;
				}
				result = ADC1BUF0;
				convert (result, bffr);


/********************************************************************************
*	Line 3																		*
*	Fill in the arguments for the fwrite function                               *
*	Note: The source should be typecast as a void *. One five-byte word should	*
*			be written from the result of the convert function					*
********************************************************************************/
				if (fwrite ((void *)bffr,1,5,myFile) != 5)
/*******************************************************************************/


				{
					// Code was unsuccessful- infinate loop
					LATA = 0xF0;
					while (1);
				}
				
				Delay (50);
			}

			while (!PORTDbits.RD13);

/********************************************************************************
*	Line 4																		*
*	Close the open file															*
********************************************************************************/
			if (fclose(myFile) != 0)
/*******************************************************************************/


			{
				// Error- infinate loop
				LATA = 0xF1;
				while (1);
			}

			else
			{


/********************************************************************************
* Line 5																		*
* Open the file in read mode													*
********************************************************************************/
				 myFile = fopen (name	,READ	);
/*******************************************************************************/
			

				if (myFile == NULL)
				{
					LATA = 0xF3;
					while (1);
				}
				while(1)
				{


/********************************************************************************
* Line 6																		*
* Read five bytes from your file into the buffer (bffr)                         *
* If the number of bytes read isn't five, break out of the loop					*
********************************************************************************/
					while (fread ((void *)bffr,1,5,myFile) == 5)
/*******************************************************************************/


					{
						mLCDHome();
						LCDwait();
						mLCDPutChar('A');
						LCDwait();	
						mLCDPutChar('/');
						LCDwait();	
						mLCDPutChar('D');
						LCDwait();	
						mLCDPutChar(' ');
						LCDwait();	
						mLCDPutChar('R');
						LCDwait();	
						mLCDPutChar('e');
						LCDwait();	
						mLCDPutChar('s');
						LCDwait();	
						mLCDPutChar(' ');
						LCDwait();	
						mLCDPutChar('=');
						LCDwait();	
						mLCDPutChar(' ');
						LCDwait();	
						mLCDPutChar(*bffr);
						LCDwait();
						mLCDPutChar(*(bffr+1));
						LCDwait();
						mLCDPutChar(*(bffr+2));
						LCDwait();
						mLCDPutChar(*(bffr+3));
						LCDwait();										
						mLCDPutChar(' ');
						LCDwait();
						mLCDPutChar('V');
						LCDwait();	
						mLCDPutCmd(0xC0);
						LCDwait();	
						
						counterBCD = toBCD (counter);

						mLCDPutChar('L');
						LCDwait();	
						mLCDPutChar('o');
						LCDwait();	
						mLCDPutChar('o');
						LCDwait();	
						mLCDPutChar('p');
						LCDwait();	
						mLCDPutChar(':');
						LCDwait();	
						mLCDPutChar(' ');
						LCDwait();							
						mLCDPutChar((unsigned char) ((counterBCD / 0x1000) + 0x30));
						LCDwait();	
						counterBCD %= 0x1000;
						mLCDPutChar((unsigned char) ((counterBCD / 0x100) + 0x30));
						LCDwait();	
						counterBCD %= 0x100;
						mLCDPutChar((unsigned char) ((counterBCD / 0x10) + 0x30));
						LCDwait();	
						counterBCD %= 0x10;
						mLCDPutChar((unsigned char) (counterBCD + 0x30));
						LCDwait();	

						display = convertback (bffr);
						LATA = display & 0xF3;
						LATD = (display & 0x0C) ? (((display & 0x0C) == 0x0C) ? 0xC0 : ((~((display & 0x0C) << 4)) & 0xC0)) : 0x00;
						Delay (50);
					}		
	

/********************************************************************************
* Line 7																		*
* Write the function to rewind your file to the beginning						*
********************************************************************************/
						rewind(myFile);
/*******************************************************************************/



						counter++;

				}
			}
		}
	}
}
				






				
void LCDwait (void)
{
	LCDProcessEvents();
	while (mLCDIsBusy())
		LCDProcessEvents();
}

void Delay(BYTE milliseconds)
{
	BYTE 	ms;
	DWORD	count;
	
	ms = milliseconds;
	while (ms--)
	{
		count = ((SYSTEM_CLOCK / 28) / 1000) - 5;

		while (count--)
		{
			;
		}
	}
	return;
}



void convert (WORD adres, char * stringres)
{
	WORD	c;
	BYTE	ones, tenths, hund;
	c = adres;
	ones = (c / 310) + 0x30;
	c %= 310;
	tenths = (c / 31) + 0x30;
	c %= 31;
	hund = (c / 3) + 0x30;
	if (hund == 0x3A)
	{
		tenths++;
		hund = 0x30;
		if (tenths == 0x3A)
		{
			tenths = 0x30;
			ones++;
		}
	}
	stringres[0] = ones;
	stringres[1] = '.';
	stringres[2] = tenths;
	stringres[3] = hund;
	stringres[4] = ',';
	stringres[5] = 0x00;
	return;
}
	
	
BYTE convertback (char * buffer)
{
	float	result = 0.00;
	
	result += ((unsigned char)buffer[0] - 0x30);
	result += (((unsigned char)buffer[2] - 0x30) * .1);
	result += (((unsigned char)buffer[3] - 0x30) * .01);
	
	if (result >= 0.00 && result <= .4125)
		return 0x01;
	if (result > .4125 && result <= .825)
		return 0x02;
	if (result > .825 && result <= 1.2375)
		return 0x04;
	if (result > 1.2375 && result <= 1.65)
		return 0x08;
	if (result > 1.65 && result <= 2.0625)
		return 0x10;
	if (result > 2.0625 && result <= 2.475)
		return 0x20;
	if (result > 2.475 && result <= 2.8875)
		return 0x40;
	if (result > 2.8875 && result <= 3.3)
		return 0x80;
	else
		return 0xff;
}

unsigned int toBCD (unsigned int old)
{
	unsigned int retval = 0x0000;
	if (old == 0x2710)
	{
		old = 0;
		return 0x0000;
	}
	retval += ((old / 1000) * 0x1000);
	old %= 1000;
	retval += ((old / 100) * 0x100);
	old %= 100;
	retval += ((old / 10) * 0x10);
	old %= 10;
	retval += old;

	return retval;
}